Overview Smartphone use has dramatically increased worldwide, contributing to a profound change in interpersonal interactions. They have become the primary medium of human interaction, and smartphone addiction, consequently, has become a modern-day reality. Recent research on smartphone addiction has provided diverse explanations regarding the correlation between gender and addiction. Therefore, this study aims to analyse the correlation and variance among smartphone addiction, gender and interpersonal attachment. Methods The participants included Taiwanese citizens and the questionnaires were randomly distributed; 1190 valid questionnaires (534 males, 656 females) were collected. Descriptive statistics were computed to observe the average value and standard deviation between interpersonal attachment and gender. Next, Spearman's ρ was conducted to interpret the correlation among smartphone addiction, gender and interpersonal attachment. Finally, the participants were divided into three groups based on their pre-determined level of smartphone addiction: high, moderate and low addictions. The Analysis of variance (ANOVA) was performed based on interpersonal attachment as the independent variable to determine any statistically significant difference among the three levels. Results There are four patterns of interpersonal attachment: secure, avoidant, dismissing and anxious attachments. The correlation analysis revealed a significant positive correlation between interpersonal attachment and smartphone addiction ( p > 0.000), while revealing no relationship between gender and smartphone addiction or gender and interpersonal attachment. Additionally, the ANOVA indicated the difference was statistically significant in the groups of high and moderate addictions; no statistical significance was identified in the group of low addiction ( p < 0.204). Conclusion This study revealed that there was no correlation between gender and smartphone addiction, but rather, a positive correlation between smartphone addiction and interpersonal attachment. This positive correlation suggests both high and moderate addiction groups display insecurity in their interpersonal attachment. Therefore, to lower the prevalence of unhealthy smartphone addiction, maintaining healthy interpersonal relationships is suggested.